Chronic coastal pollution can drive progressive mangrove degradation, yet its spatiotemporal trajectories and post-disturbance recovery remain poorly quantified from satellite observations. In this study, Landsat time-series imagery and the LandTrendr algorithm implemented on Google Earth Engine (GEE) were used to characterize mangrove responses to a kaolin pollution event in Tieshan Port, Guangxi, China. NDVI, NDMI, and NBR trajectories were first compared to identify the most sensitive indicator of contamination-induced stress, and LandTrendr was then applied to extract the timing, magnitude, duration, and spatial extent of mangrove disturbance and recovery. Results showed that kaolin contamination imposed persistent chronic stress on mangroves from 2017 to 2021, with degradation first occurring near Langen Village and then expanding northward across the port. Moderate and severe degradation were mainly distributed along tidal creeks and patch edges, indicating strong spatial control by local hydrodynamics and geomorphology. Among the tested indices, NDVI provided the earliest and clearest response to contamination, whereas NDMI and NBR showed delayed or less consistent responses. The disturbance mapping achieved an overall accuracy of 86.5% with a Kappa coefficient of 0.73. Recovery remained limited after pollution discharge ceased, suggesting persistent environmental constraints on mangrove regeneration. These findings demonstrate that Landsat–LandTrendr trajectories provide an effective framework for monitoring chronic pollution-driven mangrove degradation and recovery in coastal wetlands.

Cultural ecosystem services (CES) provide non-material benefits that support human well-being and motivate ecosystem conservation, yet their subjectivity and spatial ambiguity complicate quantitative assessment and management. Taking the Changbai Mountain tourism area as a case, we adopted the ecosystem service matrix method to assess the CES supply score based on the natural system and human system. The service coverage density was obtained through accessibility, thereby quantifying the available supply index for each tourist source area. In addition, we quantified CES demand using a questionnaire survey. Demand for 10 CES types was measured via preference ranking and integrated with the entropy weight method; statistical analysis and GIS mapping were used to examine spatial patterns and influencing factors. Results show that: (1) The overall CES demand in the Changbai Mountain tourism area exhibits clear spatial differentiation, with higher demand in the central and eastern regions and lower demand in the northwest. High-demand areas are mainly concentrated in cities relatively close to the Changbai Mountain tourism area. (2) Among individual CES, recreation (r = 6.58), natural landscapes (r = 6.35), and aesthetic value (r = 6.19) receive the highest demand, and demand structure is significantly associated with occupation, education level, consumption level, and spatial distance. The results indicate that cultural services dominated by knowledge-based services are significantly positively correlated with educational level (r = 0.549, p < 0.001). (3) CES supply capacity shows strong seasonal fluctuations, and is frequently overloaded during peak seasons, leading to prominent supply–demand conflicts; with the exception of Shenyang, Dalian, Jilin and Anshan, the other 17 cities exhibit supply–demand imbalance. By integrating multiple CES types and multiple drivers, this study reveals spatial matching patterns of CES supply and demand in a complex mountain ecotourism region and provides evidence to support ecotourism management, service capacity improvement, and sustainable development.